The present invention pertains to holders for rotary tools, and more particularly pertains to a tool driver suitable for use with acetabular reamer cups, patella cutters or other surgical tools which are secured onto a tool driver by diametrically opposed pins.
Acetabular reamer cups are surgical tools which are used to cut hemispherical cavities in pelvis bones for the insertion of artificial hip joints. Patella cutters are surgical tools, which are used to cut or shape the under side of the patella or knee cap during knee replacement surgery. A patella cutting system is generally composed of a cutter mounted on a tool driver, which in turn is mounted in the chuck or collet of a portable drill or flexible powered shaft. Cutters for patella cutting systems have a complex arrangement of precisely shaped cutting edges extending outwardly from a flat planer surface.
Unique to knee surgery and some hip operations is the utilization of milled bone, tissue and debris as filler to be placed between the artificial inser and the body to assist the healing process. Acetabular reamer cups and patella cutters are mounted on tool drivers, which in turn are mounted in the chuck or collet of a portable drill or flexible powered shaft. Both tools are separable from their tool drivers to replace or sharpen as they are used. It may be necessary to change tools during an operation, for example. Tool drivers are not inexpensive and must be cleaned and reused.
Some previous tool drivers grip the tool without the use of opposed pins by means of a flange and slot and an opposed spring-loaded ball catch, like that on a socket wrench or socket driver or other catch devices. This represents a problem in that the catch tends to trap dried blood and other debris, which is very difficult to remove during cleaning. An additional problem is that unless tolerances of tools and tool drivers are made very close, at greatly increased cost, there is considerable free play between the tool and tool driver. This increases wear and decreases the precision of the tool.
An alternative tool driver usable with acetabular reamer cups, described in Salyer, U.S. Pat. No. 4,811,632, issued on Mar. 14, 1989, has a cam and follower mechanism which provides for axial and rotary movement of a clamp. That driver avoids many of the problems presented by the ball catch, but requires a separate locking mechanism and two handed use.
The current pin type tool drivers also cannot be disassembled easily for thorough cleaning. Additionally, they have exposed trigger mechanisms which can catch and tear a surgeon's glove and are generally cumbersome to operate.
It is therefore highly desirable to provide an improved tool driver.
It is also highly desirable to provide an improved pin type tool driver which can be easily actuated to grip and release tools, such as an acetabular reamer cup.
It is also highly desirable to provide an improved pin type tool driver which can be completely disassembled for cleaning.
It is also highly desirable to provide an improved pin type tool driver which does not tend to catch bone debris.
It is also highly desirable to provide an improved pin type tool driver which can be easily joined or disjoined from an acetabular reamer cup with a single hand.
It is also highly desirable to provide an improved pin type tool driver which eliminates exposed parts which can catch and tear a surgeon's gloves, and is easily operable.
It is finally highly desirable to provide an improved pin type tool driver which meets all of the above desired features.